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Summary Objectives The present study sought to determine how basic motor skills, such as agility, and the brain's reaction to perception handling are affected by the pressure level of compression pants. Equipment and methods Twelve subjects wore three different compression pants and undertook sidestep tests to evaluate agility. For the analysis of movement-related cortical potentials, electroencephalography was conducted while participants performed an exercise involving the pressing of a foot-operated switch in response to randomly repeated sound stimuli. Results When wearing the CG2 model pants, the pant that applied the highest pressure among the three, enhanced agility (P

Pt-Pd catalysts were prepared by using the spontaneous deposition method and their characteristics were analyzed in a direct formic acid fuel cell (DFAFC). Effects of calcination temperature and atmosphere on the cell performance were investigated. The calcination temperatures were 300, 400 and 500 °C and the calcination atmospheres were air and nitrogen. The fuel cell with the catalyst calcined at 400 °C showed the best cell performance of 58.8 mW/cm2. The effect of calcination atmosphere on the overall performance of fuel cell was negligible. The fuel cell with catalyst calcined at air atmosphere showed high open circuit potential (OCP) of 0.812 V. Also the effects of anode and cathode catalyst loadings on the DFAFC performance using Pt-Pd (1: 1) catalyst were investigated to optimize the catalyst loading. The catalyst loading had a significant effect on the fuel cell performance. Especially, the fuel cell with anode catalyst loading of 4 mg/cm2 and cathode catalyst loading of 5 mg/cm2 showed the best power density of 64.7 mW/cm2 at current density of 200 mA/cm2.

In this study, we investigated the potential changes of a rectangular cross section having different aspect ratio and area. A 2D Poisson-Boltzmann equation was used to model the electric double layer field of the cross section. The potential change of the cross section was studied numerically with FEMLAB 3.0 to understand the geometry effects of the rectangular microchannel used for electroosmotic flow. According to the result, the cross-section geometry shows significant influences on the potential field. The potential distribution shows same tendency with various cross-section areas in the same aspect ratio. The potential gradient increases with the increase of the cross section area.

In this study, we investigated desulfurization abilities and activation energy using TGA for CuO-AgO sorbents calcined at 700 °C. CuO was used as a main active material and AgO was used as an additive material and 25 wt% SiO2 was used as a support material. The desulfurization reaction temperatures were 450 °C, 500 °C, and 550 °C and the regeneration reaction temperature was 700 °C. From the TGA experiments, the best sulfur loading of CAS1 sorbent containing 1 wt% AgO was about 14.95 g sulfur/100 g sorbent at 550 °C. The activation energy was calculated by the Chatterjee-Conrad method based on the TGA experiment. Desulfurization ability and activation energy of sorbent were decreased as the content of AgO increased.

We investigated the effect of temperature, oxidant and catalyst loading on the performance of direct formic acid fuel cell (DFAFC). When oxidant was changed from air to oxygen, the power density was increased to 17.3 mW/ cm2 at 25 ‡C. The power density of DFAFC operated with oxygen showed a maximum value of 40.04 mW/cm2 with the temperature rise from room temperature to 70 °C. The highest power density of DFAFC using air was observed for Pt-Ru black catalyst with loading of 8 mgPt/cm2 at room temperature. At 70 ‡C; however, the performance of catalyst with the loading of 4 mgPt/cm2 was higher than that of 8 mgPt/cm2. The DFAFC, operated with oxygen and catalyst of 4 mgPt/cm2 loading, showed the best performance at all temperature range. The enhancement of cell performance with an increase of catalyst loading is believed to come from an increase of catalyst active sites. However, operated at higher temperature or with oxygen, the cell with higher catalyst loading showed lower performance than expected. It is speculated that the thick catalyst layer inhibits the proton transport.

A series of CuO-Fe2O3 sorbents with 25 wt% SiO2 as a support were prepared based on a simple mixing method in order to evaluate the effects of Fe2O3 on their desulfurization reactivities. The initial reactivities of sorbents were tested by using a TGA and their cyclic performance was investigated in a GC/microreactor system. The activation energy calculated by the Chatterjee-Conrad method based on the TGA experiment decreased as the content of Fe2O3 increased. Sulfur loading in the cyclic reactions increased with increase of Fe2O3 content, and its maximum value was 8.9 g sulfur per 100 g sorbent.

Various CuO-based sorbents were prepared to investigate effects of sorbent ingredients such as SiO2, MnO2, and MoO3 on desulfurization reactivity. Several candidate sorbents chosen from a TGA screening test were further tested in a microreactor system. The amount of SiO2 support to minimize sintering of sorbents was 25 wt%. Sulfur loading was seriously affected by the amount of additives (MnO2, MoO3) in a multi-cycle test. Improvement of sulfur loading by the additives was observed in the multi-cycle test. Effects of support materials on sulfur loading were also investigated by using SiO2, g-alumina and zeolite. SiO2 showed the best performance among the support candidates. The sorbent showing the best sulfur loading ability was CMS6 (CuO :MoO3 : MnO2 : SiO2=61 : 11 : 3 : 25). Its sulfur loading reached up to 13.8 g sulfur/100 g sorbent in a multi-cycle test.

We report on the control of coherent optical phonon oscillations in GaN using the femtosecond pulse shaping technique. The enhancement or the discrimination of the ${E}_{2}$ phonon mode is demonstrated depending on whether or not the spectral separation of the shaped pulse matches the frequency of the phonon. The numerical calculations simulate quite well the lattice motions which are driven by shaped pulses.